The invention is situated in the field of materials handling technology and concerns a method and an installation that serve for temporary storage of objects and for delivering the objects ready for dispatch.
It is known to collect objects from stores to form consignments (e.g. on the basis of corresponding orders) and to make the consignments ready for dispatch by packaging them. For this purpose, for example, elaborate storage and consignment preparation installations are utilized. Such installations comprise a large number of storage compartments with an input and an outlet each as well as facilities for storing objects through the inputs of the storage compartments and for selectively retrieving objects through the outlets of the storage compartments. The retrieval of the objects usually takes place by consignment, i.e. the objects belonging to one consignment are retrieved from the corresponding storage compartments and are collected in a container proprietary to the installation. In large installations, it is usually possible to simultaneously retrieve objects for different consignments from the storage compartments and to collect them in corresponding containers, wherein the containers are conveyed from one storage compartment outlet to the next one along predefined paths. When all objects forming part of a consignment have been retrieved from storage compartments and are collected in a container, the container is usually transported to a packing station where complete consignments are packed and made ready for dispatch. Because the consignments established in accordance with requirements (e.g., orders) in most cases comprise differing numbers of objects, and in many cases the objects also have very different sizes, the packing step is usually at least partially carried out by hand, wherein the objects of every consignment depending on the size of the consignment are packaged in one or several dispatch units and are then addressed.
Installations for preparing consignments, such as have been briefly described above, are known, for example, from the publications EP-0627371 (or U.S. Pat. No. 5,664,928) or EP-0677459 (or U.S. Pat. No. 5,678,680).
As is easily evident from the above brief description of known installations for preparing consignments, these installations are very elaborate with respect to devices and the packing step represents a great obstacle for a complete automation, this in particular when objects of different size have to be prepared for consignment.
It is an object of the invention to create a method and an installation serving for temporary storage and ready for dispatch delivery of objects. The inventive method and installation are to enable further-reaching automation and simplification with regard to devices than known installations serving the same purpose.
According to the method in accordance with the invention, supplied objects are packed ready for dispatch individually (or, if so required, in small groups), but are kept in a condition still independent of a specific destination (e.g., unaddressed). Serving as packaging are, for example, easy to handle, closable bags which, if so required, may have different sizes. The packed objects are then individually taken over by a holding element each, the holding elements being movable along a rail system independently of one another. Packed objects together with the holding elements are then transported to a storage area and are stored there. The storage area comprises rail tracks and controllable switch points connecting the rail tracks such that the holding elements can be retrieved from the storage area as and when required essentially independent of the sequence, in which they were stored. After retrieval, the packaged objects are marked according to destination (e.g., addressed), are released from the holding elements for delivery, and are transported away. The holding elements are returned in an empty condition for taking over further objects. The holding elements are never separated from the rail system during operation.
The installation in accordance with the invention comprises an essentially closed-in-itself rail system with a multitude of holding elements movable along the rail tracks of the rail system independently of one another. The device further comprises a packing and take-over station and an addressing and delivery station. The rail system leads from the packing and take-over station along at least one feeding track to at least one storage area with storage tracks and controllable switch points, from the storage area along at least one delivery track to the addressing and delivery station, and from there for the return of empty holding elements along at least one return track back to the packing and take-over station.
The packing and take-over station is equipped for individual packing of supplied objects (or if so required of small groups of objects) and for taking over packed objects by one holding element each. The addressing and delivery station is equipped for destination-specific marking (e.g., addressing) of packed objects being supplied from the storage area and for their release from the holding elements. The at least one storage area, for example, comprises a multitude of functionally parallel rail tracks onto which and from which holding elements carrying packed objects are conveyed through correspondingly controllable switch points or switch point systems. The return track may be similarly equipped for buffering empty holding elements.
Advantageously, the holding elements and the rail tracks are constructed such that the packed objects are transported in a suspended condition and such that along descending rail tracks the force of gravity suffices for driving the holding elements. In such a case it is possible to arrange the supply track and/or the delivery track to be ascending, advantageously substantially vertically and to equip it with a suitable drive for the holding elements and to arrange substantially all other rail tracks of the rail system, in particular the rail tracks of the storage area, as descending and thus to leave the transportation on these tracks to the force of gravity.
The installation in accordance with the invention further comprises at least one computing unit receiving data concerning objects to be stored and to be delivered through corresponding data lines or through an input means. From these data the computing unit generates control data for the packing and take-over station, for the switch points of the at least one storage area, and for the addressing and delivery station. The installation can be controlled solely on the basis of the data supplied from the computing unit. It is, however, also possible to equip partial zones of the installation with sensor means and to control these autonomously, for example, to equip the packed objects and/or the holding elements with suitable identification means (e.g. a visual code or an electronic memory device) and to read the identifications for local control functions using local reading devices.
The main difference between the method according to the invention and corresponding known methods consists of the fact that according to the invention there is no assembling of consignments. According to the invention, the objects do not leave the installation in the form of consignments, but as individually packed objects that are ready for dispatch (possibly small groups of objects which, however, have never been individualized). The main advantages of the method and of the installation according to the invention result from the fact, that the packing takes place at the input side and that the objects are stored being held individually. As a result of this, at least in the case in which objects of the same or of similar format (e.g., CDs) are handled, there are no packages of different formats to be made. For handling objects with very different formats, these are supplied as usual in larger batches and, therefore, the packing and take-over station can be once adapted for the whole batch. All this makes automation easier or reduces manual labor. Because the objects are stored in a held condition, they do not have to be picked up for retrieval from the store. Therefore, an accurate positioning of the stored objects necessary for such a pick-up and/or corresponding intelligent retrieval tools is not necessary. The advantages as mentioned by far outweigh the additional packing materials and increased dispatch costs, if any.